[Nouveau] nv49 & nv4b ctx switching patch

[Stephan Schmid]

Hello

this patch is a merge of jb17bsome's nv49 patch and mine.
I have tested it for a couple of days on a nv4b and didnt get crashes.
Please rewiew and apply

Greetings
Stephan Schmid

-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: nv49_nv4b.diff
Url: http://lists.freedesktop.org/archives/nouveau/attachments/20070521/2c034463/attachment.txt